Electrode materials, in particular for applications in the field of spark-plug electrodes, have to meet extreme requirements in terms of corrosion and temperature resistance. High-melting and difficult-to-oxidize metal alloys are primarily used for this purpose. Therefore, inter alia, nickel alloys are used as the base alloy for center and ground electrodes of spark plugs. Since especially the regions of spark-plug electrodes where the actual sparking occurs must, in addition, be highly resistant to spark erosion, spark-plug electrodes are increasingly equipped with noble-metal inserts or platelets because these provide better long-term durability for the spark plug.
U.S. Pat. No. 4,743,739, for example, describes spark plugs whose center and/or ground electrodes are provided with a noble-metal containing material in their spark-forming region. For this purpose, the center electrode has one or more recesses which are filled with a noble-metal containing powder. This noble-metal containing powder is produced from a metal powder based, for example, on zirconium, which is coated with one or more layers of noble metal. The cost of such a noble-metal containing material is indeed relatively low, but it has limited resistance to spark erosion.
In contrast, an object of the present invention is to provide an electrode material that is cost-effective, but yet highly resistant to spark erosion.